In the not-so-distant future, same-sex couples may be able to have children that are biologically related to both of them. A recent article in the Journal of Law and the Biosciences outlines a new process known as in vitro gametogenesis, or IVG, through which scientists use stem cells—taken from embryos or adults—to create gametes, the technical name for eggs and sperm, regardless of gender. Scientists have already had partial success with IVG on mice, and were able to create offspring that came from a mixture of one gamete created through this new process and one created naturally.

A lesbian couple using IVG could combine one naturally produced egg with sperm created in vitro from her partner’s stem cell to create an embryo that would then be implanted in one of the their uteruses. A gay couple would go through the same process, with the egg rather than the sperm coming from the stem cell, but they would need to find a surrogate to carry the baby to term. IVG might also make it possible for embryos to be produced from multiple parents, in which genetic material from more than two people comes together to create the embryo, as well as from a single parent. In that case—probably the most perplexing from a bioethical perspective—a stem cell from an individual would be used to create whichever gamete they don’t produce naturally.

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While IVG is remarkable as a scientific breakthrough, it also represents the fast-moving, and long overdue, cultural shift that has taken place in attitudes towards same-sex parents. It wasn’t so long ago that same-sex parents couldn’t adopt one another’s biological children. Now scientists are working to help them make biological children together.

Not until 1997 did the first state, New Jersey, allow gay couples to adopt jointly, something that remains illegal only in Mississippi. It wasn’t until 2011 that the U.S. State Department updated the passport application to accommodate those with same-sex parents. And only after the Supreme Court’s 2015 ruling making same-sex marriage a right did many states begin to allow non-biological same-sex parents to adopt the children they were raising as their own.

Even with all this progress, obstacles remain for same-sex parents. Today, if same-sex parents decide to have children together but not get married, only 15 states and DC allow for second-parent (as opposed to stepparent) adoptions. Even when the parents are married, the path to dual-parent status remains tricky. In many states, a married same-sex spouse is not automatically considered the parent at birth, which is why most advocacy organizations still encourage adoption. Also, in only ten states can gay men easily and legally hire a gestational surrogate; in five states, including New York, it remains illegal.

It’s been 37 years since the first baby was born via in vitro fertilization, and while we are still wrestling with some of the ethical and legal issues surrounding the process, by and large it’s no longer considered controversial. Indeed, today IVF is being used by more couples than ever. Should IVG become a reality for humans, it’s not so hard to imagine that it will pass through the same trajectory: from something that makes us uneasy to a widely accepted path to parenthood for couples who couldn’t otherwise conceive.

Elissa Strauss writes about parenthood for Slate. Follow her on Twitter.